math arcs and sectors
TRANSCRIPT
![Page 1: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/1.jpg)
Arc length and the area of sectors
Word problem
![Page 2: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/2.jpg)
Objectives:
•To find the arc length and area of sectors
![Page 3: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/3.jpg)
![Page 4: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/4.jpg)
•“Clover Leaf ” interchanges on freeways contain four sectors.
Architecture
![Page 5: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/5.jpg)
•Computer hard drives store information in areas called sectors.
Any work field associat-ed with using computers
![Page 6: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/6.jpg)
Race track designers
•Certain measurements are required for the arc.
![Page 7: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/7.jpg)
Pie charts
•A pie chart is a circular chart divided into triangular areas.
![Page 8: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/8.jpg)
Art
![Page 9: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/9.jpg)
Dart board
![Page 10: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/10.jpg)
•To find the length of an arc:
![Page 11: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/11.jpg)
![Page 12: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/12.jpg)
•To find the area of a sector:
![Page 13: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/13.jpg)
![Page 14: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/14.jpg)
Q7 page 276
A flower bed is a quadrant of a circle.a) Find the length of edging needed for the
curved edge of the bed.b) Find the area of the flower bed.
![Page 15: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/15.jpg)
1.9
m
1.9m
![Page 16: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/16.jpg)
a)Length of arc
= 90 x 2 x 3.14 x 1.9= 2.983
Length of edging needed= 2.983m
360
![Page 17: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/17.jpg)
b) Area of sector
= 90 x 3.14 x 1.9 x 1.9= 2.83385
Area of the flower bed= 2.83385m
3602
![Page 18: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/18.jpg)
Try this
A silver earring pendant is part of a sector of a circle. Find the area of the silver.
![Page 19: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/19.jpg)
Area of the entire sector=60 x 3.14 x 16 x 16=360
133.973mm2
Area of the white part=60 x 3.14 x 12 x 12=360
75.36mm2
Area of the silver part=
= 58.613mm2
A of the entire sector – A of the white part
= 133.973 – 75.36
![Page 20: Math arcs and sectors](https://reader035.vdocuments.site/reader035/viewer/2022062308/55b87bc5bb61ebfd238b4753/html5/thumbnails/20.jpg)
More questions1)Radius: 48cm,Angle at centre: 70a) Find the arc length.b) Calculate the area of the given sector.
2) A pumpkin pie is made in a mini pie pan measuring 5 inches in diameter. It is cut into 4 equal slices. What is the area of one piece of the pie?
O